Performance analysis of peer-to-peer networks for file distribution

Peer-to-peer networks have been commonly used for tasks such as file sharing or
file distribution. We study a class of cooperative file distribution systems where a file is broken
up into many chunks that can be downloaded independently. The dierent peers cooperate
by mutually exchanging the dierent chunks of the file, each peer being client and server at
the same time. While such systems are already in widespread use, little is known about their
performance and scaling behavior. We develop analytic models that provide insights into how
long it takes to deliver a file to N clients. Our results indicate that the service capacity of
these systems growth exponentially in time and in the number of chunks a file consists of.